How do you get running apps to show up in the notification drop down menu?
Maybe there's an app for that (ugh sounds like iPhone) but I don't know of it...
However, what you'll find is that the way Android manages its programs is different than what you're used to, so it's not so critical. There are separate process manager apps out there you can explore, but Android inherently keeps the state of apps you've run active and cached in the background, and will automatically terminate old inactive ones should the memory be needed for other things.